Universal node for space frame structures
A structural apparatus for carrying loads and transferring forces to ground, the apparatus having a plurality of nodes, each having a spherical core, the core having a spherical surface. Each one of the nodes having a plurality of housing frames secured in fixed selected positions in contact with the surface. Each one of the nodes having a plurality of housing hubs secured by the housing frames in contact with the surface and free to circularly rotate about a radius of the core, and each one of the nodes has a plurality of fasteners, each of the fastener having a head and a shaft extending from the head, the head constrained between the surface and a housing hub positioning the shaft in a radial attitude relative to the core. A plurality of struts interconnect the nodes and the struts are joined with the shafts at their opposing ends.
This application is based on a prior filed provisional patent application Ser. No. 61/503,323, filed on Jul. 7, 2011 and claims international date priority therefrom. The subject matter of application 61/503,323 is hereby incorporated hereinto in its entirety.
BACKGROUNDNo federally sponsored research or development, and no sequence listing, table, or computer program listing or compact disc appendix is applicable to this application.
The field of the presently described apparatus relates to space frame structures, and particularly to node elements, fixtures where two or more struts of the frame are joined. Examples of such nodes are disclosed by Ventrella, U.S. Pat. No. 4,480,418, “Modular System for Space Grid Structures,” Cook, U.S. Pat. No. 4,974,986, “Connector for Variable-Shape Spaceframe Structural System,” Lange, U.S. Pat. No. 4,982,546, “Space Frame Node,” Lalvani, U.S. Pat. No. 5,265,395, “Node Shapes of Prismatic Symmetry for a Space Frame Building System,” and Mhaimeed, US 2002/0150444, “Special Bolt and Sleeve Combination for Use in Tube-And-Node Space Frame Systems . . . ”
A space frame is typically a lightweight rigid structure constructed from interlocking struts in a geometric pattern. Space frames can be used to span large areas with few interior supports such as columns. Like the truss, a space frame is strong because of the inherent rigidity of the triangle where flexing loads and bending moments are transmitted as tension and compression vectors along the length of each strut. The simplest form of the space frame is a horizontal slab of interlocking square pyramids which might be built from aluminum or tubular steel struts interconnected by fixtures generally referred to by the term “node.” This structure may look like the horizontal jib of a tower crane repeated many times to make it wider. A stronger form may comprise interlocking tetrahedral pyramids in which all the struts have unit length. More technically, this is referred to as an isotropic vector matrix, or in a single unit width, an octet truss. More complex variations change the lengths of the struts to curve the overall structure or may incorporate other geometrical shapes.
Space frames are common in building construction such as large roof spans in modern commercial and industrial buildings. Notable examples of buildings based on space frames include: Stansted airport in London, Bank of China Tower and the Louvre Pyramid, Rogers Centre, McCormick Place East in Chicago, Eden Project in Cornwall, England, Globen, the Swedish dome structure which has a diameter of 110 m, and Biosphere 2 in Oracle, Ariz. Large portable stages and lighting gantries are also frequently built from space frames with octet trusses. Today, the octet truss is the structure of choice for holding signs above roads in the United States.
Space frames have been used in automobile and motorcycle chassis wherein the engine and body panels are suspended, and the body panels have little or no structural function. By contrast, in a monocoque design, the body serves as the primary stress bearing and load transferring structure. Tube-frame chassis, adopted from the space frame, are frequently used in racing car designs. The first notable american-produced automobile to incorporate a space frame was the Pontiac Fiero. Fiero frames used 233 individual pieces of steel, weighing in at 6001 bs, to form a very strong and safe automobile. After the Fiero program ended in 1988, this technology was adopted for the Saturn SL series, Pontiac Trans-Sport, and Chevrolet Lumina APV mini-vans. British manufacturer TVR is particularly well known for their tube-frame chassis designs, produced since the 1950s. Other notable examples of tube-frame cars include the Audi A8, Lotus Seven, Ferrari 360, Lamborghini Gallardo, and Mercedes-Benz SLS AMG.
BRIEF SUMMARY AND OBJECTIVESThe presently described apparatus is a highly novel node which is used as an essential joining element in the construction and operation of space frames of the types previously mentioned. The node is an assembly of several distinct parts or elements including a spherical core, at least one, and generally several, housings, and fasteners. Each housing is made-up of a housing frame, and a housing hub. Generally, one end of each space frame strut is engaged with one of the fasteners so that the node is the meeting point of struts coming to the node from different directions. In practice, the node may be a terminal point of a space frame, or it may join two or more struts of the space frame.
In one aspect of the presently described apparatus, the longitudinal axes of all struts which are joined to the node pass through a common point which is the geometrical center of the node's spherical core. This avoids the possibility of force moments on, or within, the node. This very important capability enables the node to pass tensile and compressive forces along the space frame without unwanted stress being applied to the node itself and without generating bending or shear forces on the struts or their interconnections with nodes.
In another aspect of the apparatus, the axis of each fastener is on a radius of the core and movable within a range of angular positions all the while remaining co-radial with the core. Of course, this accounts for the benefit described in the preceding paragraph.
In another aspect of the apparatus, the angular range of positions of each one of the fasteners may be between 45° and 90°.
In another aspect of the apparatus, each of the fasteners may have a threaded stud or a threaded hole and may be rotatable about its radially aligned axes thereby providing a simple and quick means for securely attaching the one end of a strut to the fastener wherein the strut may be adapted for threadedly engaging the fastener.
In another aspect of the apparatus, each one of the housing hubs may be rotatable enabling its engaged fastener to be moved to any position within a solid angle having a cone outer surface defined by the angular range of the possible extreme positions of the fastener.
The details of one or more embodiments of these concepts are set forth herein and other features, objects, and advantages of these concepts will be apparent to those of skill in the art from this writing and drawings, and from the claims.
Like reference symbols in the various drawings indicate like elements.
DETAILED DESCRIPTIONIn
Strut 5 may be made of a metal such as aluminum or steel, or alternately may be formed of a plastic, fiber composite, glass or other structural material. The primary requirement of strut 5 is that it must be able to transfer a tensile load without stretching or breaking, and also must be able to handle a compressive load without bending, collapsing or snapping in shear. As to how much load a given strut 5 will handle depends upon design factors such as weight distribution in the space frame, wind loads, kinetic loads due to moving the space frame, local loads applied as for instance by: lighting fixtures, heaters, speakers, skin plates, or signs, which may be attached to or hung from the space frame.
In the cross-sectional view of
Housing hub 40, as shown in
In
In
Embodiments of the subject apparatus and method have been described herein. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and understanding of this disclosure. Accordingly, other embodiments and approaches are within the scope of the following claims.
Claims
1. A structural apparatus for transferring forces, the apparatus comprising:
- a spherical core having a spherical surface;
- a housing frame fixed to the spherical surface, the housing frame having a circular aperture therein;
- a housing hub within the circular aperture, the housing hub restrained by the housing frame to sliding rotational contact with the spherical surface, the housing hub having a slot therein; and
- a fastener restrained by the slot of the housing hub to movement in contact with the spherical surface over a range of radial positions within the slot relative to the spherical core; whereby
- a combination of the rotational contact of the housing hub, and the range of radial positions of the fastener enable alternative positioning of the fastener within a solid angle.
2. A structural apparatus for transferring forces, the apparatus comprising:
- a spherical core having a spherical surface;
- a plurality of housing frames fixed to the spherical surface, the housing frames each having a circular aperture therein;
- a plurality of housing hubs, each within the circular aperture of a housing frame and restrained by the housing frame to sliding rotational contact with the spherical surface, the housing hubs each having a slot therein; and
- a plurality of fasteners, each restrained by the slot of a housing hub to movement in contact with the spherical surface over a range of radial positions within the slot relative to the spherical core; whereby
- a combination of the rotational contact of the housing hubs, and the range of radial positions of the fasteners enable alternative positioning of each of the fasteners within a solid angle.
3. A structural apparatus for transferring forces, the apparatus comprising:
- a plurality of nodes;
- each said one of the nodes having: a spherical core with a spherical surface: a plurality of housing frames fixed to the spherical surface, the housing frames each having a circular aperture therein; a plurality of housing hubs, each within the circular aperture of a housing frame and restrained by the housing flame to sliding rotational contact with the spherical surface, the housing hubs each having a slot therein; and a plurality of fasteners, each restrained by the slot of a housing hub to movement in contact with the spherical surface over a range of radial positions within the slot relative to the spherical core; whereby a combination of the rotational contact of the housing hubs, and the range of radial positions of the fasteners enable alternative positioning of each of the fasteners within a solid angle a plurality of struts, each of the struts engaged at each end thereof with a one of said fasteners thereby joining two of the nodes for transferring forces between the spherical centers of the nodes.
3632147 | January 1972 | Finger |
3857212 | December 1974 | Barnett |
4027449 | June 7, 1977 | Alcalde Cilveti |
4131380 | December 26, 1978 | De Bliquy |
4480418 | November 6, 1984 | Ventrella |
4974986 | December 4, 1990 | Cook |
4982546 | January 8, 1991 | Lange |
5069572 | December 3, 1991 | Niksic |
5095677 | March 17, 1992 | Godbout et al. |
5265395 | November 30, 1993 | Lalvani |
5797695 | August 25, 1998 | Prusmack |
6378265 | April 30, 2002 | Konstandt |
7896016 | March 1, 2011 | Shi |
20020150444 | October 17, 2002 | Mhaimeed |
Type: Grant
Filed: Jul 2, 2012
Date of Patent: Sep 2, 2014
Inventor: Alexis Rochas (Los Angeles, CA)
Primary Examiner: Jessica Laux
Application Number: 13/540,449
International Classification: E04H 12/00 (20060101); E04B 7/08 (20060101); E04B 1/19 (20060101);